There are four lights! January 27, 2014

It’s hard being a physicist. Pretty much every place you look, you’re seeing some cool physical phenomenon that just screams, “Newton (or some other dead guy) discovered me!” If you’re lucky, the screaming isn’t followed by an apple hitting you on the head. Unless you’re a Klingon who is reciting love poetry; then that might be lucky.

Anyway, one such event occurred when I was looking into my coffee mug, which happened to be filled with hot water and a touch of coconut oil for flavor (and medium-chain triglycerides). Some bubbles were sitting there on the surface, breaking up the layer of oil, and behaving like a lens. There was an interesting image on the bottom of the cup, which you can see below.

As you can see, underneath each bubble, there appears to be something that almost looks like a four on a six-sided die. It took me a second to figure out what was going on. Then I realized that, directly above me, were four lights. If I shift my angle, you can see them quite clearly in the reflection, though the one on the bottom left is partially blocked by my phone.

This was surprising to me because this lamp is newly installed. Our previous lamp in this room had only one light. It took me a bit to realize that this was why I was so surprised to see an image in the bottom of my cup: it really was something new.